Device for sketching and cutting out segments of metal



April 19, 1966 F. GIERLICH 3,246,398

DEVICE FOR SKETCHING AND CUTTING OUT SEGMENTS OF METAL Filed 001). 17,1963 INVENTOR f?" Liz 6 L67" blah ATTORNEYS United States Patent3,246,398 DEVICE FOR SKETCHING AND CUTTING 'OUT SEGMENTS 0F METAL FritzGierlich, 29 Kalkumer Str., 4034 Angermund, Bezirk Dusseldorf, GermanyFiled Oct. 17, 1963, Ser. No. 316,982 3 Claims. (CI. 33-21) Sphericalcontainers used for storing gas under pressure, or as reservoir forwater or the like, are usually constructed of steel plate segments. Todate, these segments have been cut out, for the particular case andrequirements by a trial and error method, of even plates with a sizecorresponding to rim allowance. After flanging of the plates to theprearranged radius, there occurs the finishing cutting of the segmentsby hand or according to pattern. Despite this there are stillconsiderable inaccuracies so that in most cases a further cutting duringconstruction is unavoidable.

It is an object of the present invention to produce a device in which,from flanged plates at a required spherical radius, spheric segmentplates can be sketched or cut out correctly as to rim and anglesketched.

This problem is solved by having a collar positioned about a turnable orrotatable Cardanic ring system concentric to a supported pivotedoperating arm which is supported over a raw partial ball which is to beformed into the finished segment.

The device consists essentially of a Cardanic ring system, containingthree or four rings, which is supported by a collar situated onsupports, wherein the inner ring of the Cardanic ring system has aswivel arm arranged concentrically stationary and perpendicularly on aturnable shaft so that it pivots about the shaft axis. This swivel arm,the lower point of which serves for sketching, can also be replaced by acorrespondingly arranged metal cutting burner. According to a fiangingof the plates to be undertaken before the sketching and cutting, it ispossible with the help of this device to sketch and cut segments with anunexpectedly high theoretical precision.

Other objects and advantages of the invention will become apparent froma study of the following description and drawing wherein:

FIGURE 1 is a perspective of the apparatus according to the invention;

FIGURE 2 is a top view of the apparatus of FIGURE 1; and

FIGURE 3 is a section taken along lines 33 of FIG- URE 2.

As seen in FIGURES 1-3 of the drawing, four leg supports A which areresistant to bending are flexibly secured at their upper ends at anupper collar B and at their lower ends to a base plate G. The length ofthe supports A can be varied since the legs are of the telescopic type.These legs support collar B which in turn supports a Cardanic ringsystem C. This ring system consists of rings D D D and D (FIGURE 2),which in the known Cardanic fashion are supported in a swiveling mannerby pins in order always to be staggered at 90 from each other and withineach other. As shown in the drawings, pin locking means are provided inthe system such as illustrated for shaft E on ring D, and on the pinbetween rings D and D The outer ring D rests turnably in collar B. Theinnermost ring D displays a turnable shaft E to which a telescopicallyextendable swivel arm F is arranged concentrically, perpendicularly andstationary toward the bottom portion of the apparatus. The legs A reston base plate G at which a three-point support H is provided as thesupport for the segment plates which support is changeable for fittingto the actual radius. It should be pointed out that 3,246,398 PatentedApr. 19, 1966 the supporting legs A are exchangeable or changeable intheir length.

From most of the skin sections of the sphere, it can be seen that forthe format and arrangernent of the segment plates the spheric biangularsystems are the basis from which are obtained the number of segments.Complete spherical biangles, for example, extending from pole to pole,are undesirable, because of the difiic-ulties arising from soldering.Therefore, spherical biangular formats are preferred where the longpointed end pieces have been omitted. Hence, the necessity arises toprovide more than one segment format, and it has also been possible todevelop divisions which in such cases come out with two or three segmentsizes. However, from the number of the spheric biangles constituting thebasis of the division, corresponding spheric center angles canconstantly be achieved which are necessary for the introduction of theindividual rings of the Cardanic ring system of the device according tothe invention. With the arrangement of the rings to these angles, whicharrangement is effected by the deviation from the horizontal position,the arrangement of the swivel arm is necessarily also connected. By thefixed motion of the swivel arm, the cutting and sketching head indicatesthe cutting line by swinging on the underlying metal. It is inaccordance with the invention to bring a raw segment metal correspondingin form and size as concentrically as possible under the Cardanic ringsystem. The pivotable rings are then manipulated so that arm F isinclined to move about the axis of shaft E in such a manner as tocontact the raw segment along a predetermined line defining the boundaryof the finished segment. Accordingly, by proper angular arrangement ofthe rings, a side of the segment is formed. As a result, with thisproper positioning of the rings with respect to each other and byrotation of the entire system in collar B, it is possible to form aspherical segment without the necessity of disturbing the mounting ofthe device or of the workpiece.

The Cardanic ring system represented with four rings in the processexample of the present device can naturally also exist with three rings.In the arrangement of three rings (D D D the outer ring (D together withthe collar B takes over the function of the outer ring existing withfour rings. The arrangement of four rings, however, simplifies thedislocation (turning of the total ring system.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is, therefore, to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

Thus the Cardanic ring system, instead of being supported by legs, canbe mounted, for instance, hanging down without vibration from theceiling of a factory hall. In order to make possible a remote control incase of large distances between metal and Cardanic ring systemmechanical or electric preselccting and control devices can be providedfor adjusting the ring system.

What is claimed is: v

1. A device for forming spherical segments comprising a collar, aCardanic ring system including an inner ring, an outer ring and at leastone intermediate ring, said outer ring being rotatably mounted in saidcollar, pivot means securing each of said rings to its adjacent rings,the pivot means between each pair of said rings being 90 apart from thepivot means of the adjacent pair of rings, a shaft extendingdiametrically across said inner ring, an operating arm rotatably mountedon said shaft with said shaft constituting the axis of rotation of saidarm, locking means in said inner for fixing said shaft relative to theinner ring and locking means on said intermediate ring for fixing theinner ring relative to the intermediate ring, a cutting instrumentdisposed at the end of said operating arm, a base plate, a three-pointedsupport on said base plate for a concentric seating of a work pieceunder the center of said Cardanic ring system with said cuttinginstrument disposed slightly above said support whereby said cutting instrument may contact the workpiece to form a spherical segment out ofsaid workpiece, and support means for mounting said collar above saidbase plate;

2. A device as set forth in claim 1 wherein said support means formounting said collar above said base plate comprises a plurality oftelescopic legs connected at one 15 end to said base plate and at theother end to said collar.

3. The device according to claim 1 wherein said Cardanic ring systemincludes four individual rings.

References Cited by the Examiner UNITED STATES PATENTS 2,368,853 2/1945Levaggi 3324 2,474,149 6/1949 Hume 3321 2,746,152 5/1956 Deakin 3324 XFOREIGN PATENTS 234,867 5 1911 Germany. 325,920 4/1935 Italy.

ISAAC LISANN, Primary Examiner.

1. A DEVICE FOR FORMING SPHERICAL SEGMENTS COMPRISING A COLLAR, ACARDANIC RING SYSTEM INCLUDING AN INNER RING, AN OUTER RING AND AT LEASTONE INTERMEDIATE RING, SAID OUTER RING BEING ROTATABLY MOUNTED IN SAIDCOLLAR, PIVOT MEANS SECURING EACH OF SAID RINGS TO ITS ADJACENT RINGS,THE PIVOT MEANS BETWEEN EACH PAIR OF SAID RINGS BEING 90* APART FROM THEPIVOT MEANS OF THE ADJACENT PAIR OF RINGS, A SHAFT EXTENDINGDIAMETRICALLY ACROSS SAID INNER RING, AN OPERATING ARM ROTATABLY MOUNTEDON SAID SHAFT WITH SAID SHAFT CONSTITUTING THE AXIS OF ROTATION OF SAIDARM, LOCKING MEANS IN SAID INNER RING RELATIVE TO THE RELATIVE TO THEINNER RING AND LOCKING MEANS ON SAID INTERMEDIATE RING FOR FIXING THEINNER RING RELAWTIVE TO THE INTERMEDIATE RING, A CUTTING INSTRUMENTDISPOSED AT THE END OF SAID OPERATING ARM, A BASE PLATE, A THREE-POINTEDSUPPORT ON SAID BASE PLATE FOR A CONCENTRIC SEATING OF A WORK PIECEUNDER THE CENTER OF SAID CARDANIC RING SYSTEM WITH SAID CUTTINGINSTRUMENT DISPOSED SLIGHTLY ABOVE SAID SUPPORT WHEREBY SAID CUTTINGINSTRUMENT MAY CONTACT THE WORKPIECE TO FORM A SPHERICAL SEGMENT OUT OFSAID WORKPIECE, AND SUPPORT MEANS FOR MOUNTING SAID COLLAR ABOVE SAIDBASE PLATE.